<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../vue.js"></script>

</head>
<body>
    <!-- 添加了v-once属性后，值不会变化 -->
    <div id="app">
       <div >hello{{count}}</div>
       <div v-once>abc{{count}}</div>
       <button @click="count++">累加</button>
       
       <div v-pre>def{{count}}</div>
    </div>
    <script>
        Vue.config.productionTip = false;
        const vm = new Vue({
            el:'#app',
            data(){
                return {
                    msg1:'hello',
                    msg2:'<a>a标签</a>',
                    count:2
                }
            }

        })
    </script>
</body>
</html>